Fluid pressure engaged clamping fixture



Feb 24,- m- N. M. MARSILIUS FLUID PRESSURE ENGGED CLAMPING FIXTURE Filed Dec.

s' sheets-sheet 1 Feb. 24, 1948.

N; M. MARSILIUS FLUID PRESSURE ENGAGED CLAMPING FIXTURE Fi1 e d Dc. e, 1944 3 shetS-sheet A.2

INVENToR. Newman MMarsz'Iz'us BY 1948. N. M. MARslLlUS FLUID PRESSURE ENGAGED CLAMPING FIXTURE Feb. 24,

Filed Dec. e,- 1944 3 sheen-shewl 5 Ill il n w INVENTOR, Newman' MMclrsIus Patented Feb. 24, 1948 Newman M ..'Marslns,v`t'1krumbull, Conn. s Application December 6, 1944, Serial No. 566,924

. This invention relates'to new and useful improvements in work clamps and has particular relation to a clamping fixture including a fluid pressure means for causing a clamping block to vhold a piece of work tightly against a base.

The objects and'advantages of the invention '4 will become apparent from a consideration of the following detailed description taken in connection with theaccompanying drawings wherein Va satisfactory embodiment of the invention f is shown. However, it is to be understood that the invention is not limited to the details disclosed but includes all such variations and modications as fall within the spirit of the invention and the scope of the appended claims.

Inthe drawings- Fig. 1 is a top planview of the clamping lixture of the invention;

Fig, 2 is a front elevational view thereof ;V

Fig. 3l is a sectional view taken as along the line 3-3 of Fig. 2; Fig. 4 is a vview partly in elevation and partly in section and taken substantially as along'the line II-f4 of Fig. 1;

Fig. 5 is a diagrammatic view illustrating the various passages of the hydraulic system employed in the present clamp; and f Fig. 6 is an enlarged detail sectional vie taken as along the line 6-6 of Fig. 3.

Referring in detail to the drawings the clamping fixture of the invention comprises a base generally designated I'Il and a clamping block `I I movable toward and from said base to clamp work thereagainst. Shown as integral with, although they may be separately formed and secured to, the bas@l I0, are endwalls I2 and I3, each comprising a frame portion including a rear post I4, a front post I5 and an outer or upper bar-like part I6 connecting the posts I4 andv I5. End plates II .and I8 are secured to the frame portions of the end walls I2 and I3, respectively. Plates I1 and I8 are removably secured in place as by machine screws I9 whereby such plates may .be changed. While these plates are shown blank vin the -drawings they may support drill bushings, or the like as will be set forth in connection Iwiththe clamping block I I. i Pivotally mounted at the front of the base I0, ason a bar 20, is a front wall 2| kwhich together with-the end walls I2 and I3 and the base forms a box-jig.` Front wall 2| is removable and may be provided with drill bushings or the like as. will be; described in connection with the clamping block I I. The front wall 2l isadapted to be swung sathgprqt .Der 20, t0. an out or. the. way mation.

4 claims. (o1. 1544-290) ,as suggested by the dotted lines in Fig. 3, whereby to permit of the placing of work on and the removing of work fromthe top or upper side of the base I0.

Wall 2l ts between the front frame posts I5 of the end walls when in closed position and at outward swinging movement but may be released by a turn of the screws or buttons 24. It is held against inward swinging movement by engagement with the front edge of base I'Il (see Fig. 3)

vand by engagement of its lugs 22 with the front ends of the` top or connecting bars I 6 of the end frames.

Clamping block Il is mounted' on a pair of posts 25 and 26 reciprocable inwardly and outwardly with respect to the base I0. Posts 25 and 26 pass through the clamping block and the latter is split through to its edges as at 21 from its openings receiving the posts. Screws 28 passing through the split portions 21 ofthe block are adapted to be tightened to cause the block to bind tothe posts.

From this it will be clear that on loosening of screws 286the block may be adjusted inwardly or outwardly of or on the posts and that thereafter ,on tightening of the screws 28 the block is secured or fixed-in adjusted position. Block II is positionedon the posts 25 and 26 according to the size of the work to be clamped, where a run of the'same piece is to be handled, whereby a minimum movement of the block will bring it into clamping relation the base.

Post 25 operates in an opening or socket 29 in with a piece of work on vvthe base while the inner end of post 26 operates 'in a cylinder 3|) also in the base I0. The posts are guided and steadied by hollow bosses 3| and 32, respectively, formed with and extending outwardly from the base I0. Boss 32 includes a hollow lateral extension 33 through which extends a shaft 34 having a short lever or motivating link 35 keyed thereto as at 36. Lever 35 includes a hub portion 31 surrounding and keyed to the shaft and an arm portion extending radially of the shaft and having `l`a ball-like portion 38 at its outer end received or located within an opening or socket 39 in the post 26.

To the outer end of shaft 34 is keyed or otherwise xed a relatively long handle or lever 40. Clearly on movement of the hand lever 40 to turn .the yshaft ,3.4. thelever oxlinkv 35 will be moved the booster screw 68 is backed off and the push rod 64 operated to unseat the valve 54. Thereupon as the hand lever 40 is moved in a reverse direction to raise the clamping block Il the fluid is forced from the cylinder 30 above the piston out through the port 5l, along through passages 5B, 58 and 59, past the unseated valve 54 and through the hollow plug 48 into the passage 63 and from the latter through passages 62 and 60 and the port 6| into cylinder 30 at the lower or inner side of piston 44.

The mechanical advantage of the booster screw 68 and its operating means, namely the Allen wrench 1l, depends on the threads of said screw and the length of the wrench lever or handle. Since the entire hydraulic system disclosed is filled with oil or the like and the latter is relatively incompressible it will be seen that the final pressure applied to the work through the clamping block Il by turning of the screw 68 inwardly will be very large.

In Fig. 3 the passages 56, 58 and 59 are rather diagrammatically shown and the same is true with respect to the passages 63, S2 and 69. In Fig. 5 which diagrammatically and at a glance shows the hydraulic circuit the passages 6l and 13 are combined but it will be understood that this is only for the purpose of making the diagram easy to read. In this figure a knurled head 89 has been substituted for the Allen wrench. However from this figure it will be clear that when the valve 54 is closed and the booster piston is fed inwardly there is no escape for the liquid and a great pressure is built up in the upper end portion of the cylinder 30 so that any work on the base l0 is very effectively clamped in place.

Having thus set forth the nature of my invention, what I claim is:

1. In a clamping xture, a base, a post movable inwardly and outwardly with respect to said base, a clamping block on said post, a cylinder in said base, a piston on said post and operating in said cylinder, a lever mechanically connected to said post and manually operable to move the same inwardly and outwardly with respect to said base, said base having passages therein providing for the movement of fluid between the inner and outer sides of said piston as the latter and post are moved, a valve controlling such movement of fluid in said passages, means operable from said lever for unseating said valve, and a separate manually operable booster means for increasing the pressure of the fluid at the outer side of said piston when the valve is seated.

2. In a clamping fixture, a base, a post movable inwardly and outwardly with respect to said base, a clamping block on said post, a cylinder and piston construction of which the piston is connected to move with said post, manually operable means for moving said post inwardly and outwardly with respect to said base, means providing passages for the movement of fluid to and from the inner and outer sides of said piston as said port and piston are moved, and a separate manually operable booster means for increasing the pressure of the uid at the outer side of said piston when the post is in an inner position with said clamping block against a piece of work.

3. In a clamping xture, a base, a post movable inwardly and outwardly of said base and in all positions extending into the latter, a cylinder in said base and into which said post extends, a piston on said post within said cylinder, a normally seated valve, said base having a passage therein from the outer portion of said cylinder to said valve and a passage from the inner portion l of said cylinder to said valve whereby when the latter is unseated the inner and outer portions of the cylinder are in communication, manually controlled means for unseating said valve, a lever connected to move said post and thereby said piston when the valve is unseated and thereby force fluid through said passages from one side to the other of the piston, a boost-er cylinder in said base, said base having a passage therein connecting the inner` end of said booster cylinder with the outer end portion of the rst cylinder, said base having a passage therein connecting the outer end of the booster cylinder with the inner end portion of the first cylinder, a booster piston in said booster cylinder, and manually operable means for moving said booster piston linwardly in said booster cylinder to increase the pressure of the uid in the outer end portion of the rst cylinder when said post has been moved inwardly and said valve is seated.

4. In a clamping iixture, a base, a post movable inwardly and outwardly of said base and in all positions extending into the latter, a cylinder in said base and into which said post extcnds, a piston on said post Within said cylinder, a normally seated valve, said base having a passage therein from the outer portion of said cylinder to said valve and a passage from the inner portion of said cylinder to said valve whereby when the latter is unseated the inner and outer portions of the cylinder are in communication, manually controlled means for unseating said valve, a lever connected to move said post and thereby said piston when the valve is unseated and thereby force fluid through said passages from one side to the other of the piston, a booster cylinder in said base, said base having a passage therein connecting the inner end of said booster 'cylinder with the outer end portion of the first cylinder, said base having a, passage therein connecting the outer end of the booster cylinder with the inner end portion of the first cylinder, a booster piston in said booster cylinder, a screw for moving said booster piston in said booster cylinder, a manually operable means providing a mechanical advantage for turning said screw, and said screw adapted when turned in one direction to feed said booster piston inwardly in said booster cylinder to increase the pressure of the fluid in the outer portion of the first cylinder when said post has been moved inwardly and said valve is seated.

NEWMAN M. MARSILIUS.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 198,176 Alexander Dec. 18, 1877 381,263 Liddell Apr. 1'?, 1888 705,097 Koken July 22, 1902 775,853 Philipp Nov. 22, 1904 1,142,704 Haugh June 8, 1917 1,250,558 Burns Dec. 18, 1917 1,575,039 Cooper Mar. 2, 1926v 1,643,591 Smith Sept. 27, 1927 1,659,157 Prouty Feb. 14, 1928 1,827,258 Payzant Oct. 31, 1931 2,061,369 Prendergast et al. Nov. 17, 1936 2,107,970 Wells Feb. 8, 1938 2,396,539 Smith `Mar. 12, 1946 

